TY - CHAP
T1 - Characterization of the Sedimentation Associated with the emDeepwater Horizon/em Blowout: Depositional Pulse, Initial Response, and Stabilization
AU - Larson, Rebekka A.
AU - Brooks, Gregg R.
AU - Schwing, Patrick
AU - Diercks, Arne R.
AU - Holmes, Charles W.
AU - Chanton, Jeffrey P.
AU - Diaz-Asencio, Misael
PY - 2019/6/1
Y1 - 2019/6/1
N2 - The Deepwater Horizon (DWH) blowout led to a depositional pulse in the northeast Gulf of Mexico in the Fall of 2010 associated with an observed Marine Oil Snow Sedimentation and Flocculent Accumulation (MOSSFA) event. A time series (2010–2016) of annually collected sediment cores at four sites characterize the sedimentary response to the event, post-event, and stabilization/recovery. The depositional pulse (2010–2011) was characterized by high sedimentation rates with little to no bioturbation and large excursions in % silt. The lack of changes in sediment composition indicate that the same sediment sources dominated during the event, but the rates of sedimentation increased. In the years following the event (2011–2012), sedimentation rates were lower, and bioturbation was absent, and the initial excursions in % silt began to become undetectable in the sedimentary record. Between 2013 and 2016, a spatially and temporally variable return of bioturbation was detected at most sites. Sedimentation rates at all sites remained low, but increases in 234 Th xs apparent mass accumulation rates indicated a return of bioturbation and potential stabilization and/or recovery of the sedimentary system. The deepest site (~1500 m) did not have any indication of bioturbation as of the 2016 collections, which may reflect a lack of recovery or that bioturbation was never present. In 2012, 210 Pb xs age dating began to resolve the depositional pulse suggesting it may be applied to determine changes in the pulse deposit over time, and/or its preservation in the sedimentary record. Factors that may influence preservation include burial, bioturbation, degradation of the pulse signature, and remobilization of pulse sediments.
AB - The Deepwater Horizon (DWH) blowout led to a depositional pulse in the northeast Gulf of Mexico in the Fall of 2010 associated with an observed Marine Oil Snow Sedimentation and Flocculent Accumulation (MOSSFA) event. A time series (2010–2016) of annually collected sediment cores at four sites characterize the sedimentary response to the event, post-event, and stabilization/recovery. The depositional pulse (2010–2011) was characterized by high sedimentation rates with little to no bioturbation and large excursions in % silt. The lack of changes in sediment composition indicate that the same sediment sources dominated during the event, but the rates of sedimentation increased. In the years following the event (2011–2012), sedimentation rates were lower, and bioturbation was absent, and the initial excursions in % silt began to become undetectable in the sedimentary record. Between 2013 and 2016, a spatially and temporally variable return of bioturbation was detected at most sites. Sedimentation rates at all sites remained low, but increases in 234 Th xs apparent mass accumulation rates indicated a return of bioturbation and potential stabilization and/or recovery of the sedimentary system. The deepest site (~1500 m) did not have any indication of bioturbation as of the 2016 collections, which may reflect a lack of recovery or that bioturbation was never present. In 2012, 210 Pb xs age dating began to resolve the depositional pulse suggesting it may be applied to determine changes in the pulse deposit over time, and/or its preservation in the sedimentary record. Factors that may influence preservation include burial, bioturbation, degradation of the pulse signature, and remobilization of pulse sediments.
KW - Sediment
KW - Chronology
KW - MOSSFA
KW - Short-lived radioisotopes
KW - Sedimentation
UR - https://digitalcommons.usf.edu/msc_facpub/458
UR - https://doi.org/10.1007/978-3-030-11605-7_14
U2 - 10.1007/978-3-030-11605-7_14
DO - 10.1007/978-3-030-11605-7_14
M3 - Chapter
BT - Deep Oil Spills Facts, Fate, and Effects
ER -